The present invention relates to seals, and in particular, to a hinged seal for use in a gas turbine engine.
Gas turbine engines operate according to a continuous gas flow. Air enters the gas turbine engine through a fan section and is pressurized in a compressor section. From the compressor section, the pressurized air enters a central combustor section where fuel is added and the air is ignited. Air from the combustor then expands through a turbine section where bladed rotors convert the thermal energy into mechanical energy to rotate one or more centrally mounted shafts that drive the compressor section. Due to their compact and powerful nature, gas turbine engines are suitable for powering aircraft, heavy equipment, ships, and electrical power generators. Seals are often used in gas turbine engines to discourage certain airflow and seal off cavities from one another.
Finger seals are the most common type of seal found in gas turbine engines. The typical finger seal includes two pieces of thin sheet metal containing numerous slits, the two pieces being offset in order to prevent alignment of the slits. Finger seals can accommodate high pressure, but may not be able to accommodate a long sealing span with a large offset between the two components to be sealed. Hinged seals may also be found in gas turbine engines. The typical hinged seal includes a thick metal stand containing a hinge pin. The hinged seal can withstand high pressure and a large offset between the two components to be sealed. However, hinged seals are prone to high leakage because they require clearance gaps in order to freely rotate. A seal that can withstand high pressure and high temperature while also withstanding a large offset and reducing leakage would be advantageous.